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Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0-only */
2/*
3 * Copyright (C) 2009 Chen Liqin <liqin.chen@sunplusct.com>
4 * Copyright (C) 2012 Regents of the University of California
5 */
6
7#ifndef _ASM_RISCV_PGALLOC_H
8#define _ASM_RISCV_PGALLOC_H
9
10#include <linux/mm.h>
11#include <asm/sbi.h>
12#include <asm/tlb.h>
13
14#ifdef CONFIG_MMU
15#define __HAVE_ARCH_PUD_FREE
16#include <asm-generic/pgalloc.h>
17
18/*
19 * While riscv platforms with riscv_ipi_for_rfence as true require an IPI to
20 * perform TLB shootdown, some platforms with riscv_ipi_for_rfence as false use
21 * SBI to perform TLB shootdown. To keep software pagetable walkers safe in this
22 * case we switch to RCU based table free (MMU_GATHER_RCU_TABLE_FREE). See the
23 * comment below 'ifdef CONFIG_MMU_GATHER_RCU_TABLE_FREE' in include/asm-generic/tlb.h
24 * for more details.
25 */
26static inline void riscv_tlb_remove_ptdesc(struct mmu_gather *tlb, void *pt)
27{
28 if (riscv_use_sbi_for_rfence()) {
29 tlb_remove_ptdesc(tlb, pt);
30 } else {
31 pagetable_dtor(pt);
32 tlb_remove_page_ptdesc(tlb, pt);
33 }
34}
35
36static inline void pmd_populate_kernel(struct mm_struct *mm,
37 pmd_t *pmd, pte_t *pte)
38{
39 unsigned long pfn = virt_to_pfn(pte);
40
41 set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
42}
43
44static inline void pmd_populate(struct mm_struct *mm,
45 pmd_t *pmd, pgtable_t pte)
46{
47 unsigned long pfn = virt_to_pfn(page_address(pte));
48
49 set_pmd(pmd, __pmd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
50}
51
52#ifndef __PAGETABLE_PMD_FOLDED
53static inline void pud_populate(struct mm_struct *mm, pud_t *pud, pmd_t *pmd)
54{
55 unsigned long pfn = virt_to_pfn(pmd);
56
57 set_pud(pud, __pud((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
58}
59
60static inline void p4d_populate(struct mm_struct *mm, p4d_t *p4d, pud_t *pud)
61{
62 if (pgtable_l4_enabled) {
63 unsigned long pfn = virt_to_pfn(pud);
64
65 set_p4d(p4d, __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
66 }
67}
68
69static inline void p4d_populate_safe(struct mm_struct *mm, p4d_t *p4d,
70 pud_t *pud)
71{
72 if (pgtable_l4_enabled) {
73 unsigned long pfn = virt_to_pfn(pud);
74
75 set_p4d_safe(p4d,
76 __p4d((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
77 }
78}
79
80static inline void pgd_populate(struct mm_struct *mm, pgd_t *pgd, p4d_t *p4d)
81{
82 if (pgtable_l5_enabled) {
83 unsigned long pfn = virt_to_pfn(p4d);
84
85 set_pgd(pgd, __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
86 }
87}
88
89static inline void pgd_populate_safe(struct mm_struct *mm, pgd_t *pgd,
90 p4d_t *p4d)
91{
92 if (pgtable_l5_enabled) {
93 unsigned long pfn = virt_to_pfn(p4d);
94
95 set_pgd_safe(pgd,
96 __pgd((pfn << _PAGE_PFN_SHIFT) | _PAGE_TABLE));
97 }
98}
99
100#define pud_free pud_free
101static inline void pud_free(struct mm_struct *mm, pud_t *pud)
102{
103 if (pgtable_l4_enabled)
104 __pud_free(mm, pud);
105}
106
107static inline void __pud_free_tlb(struct mmu_gather *tlb, pud_t *pud,
108 unsigned long addr)
109{
110 if (pgtable_l4_enabled)
111 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(pud));
112}
113
114static inline void __p4d_free_tlb(struct mmu_gather *tlb, p4d_t *p4d,
115 unsigned long addr)
116{
117 if (pgtable_l5_enabled)
118 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(p4d));
119}
120#endif /* __PAGETABLE_PMD_FOLDED */
121
122static inline void sync_kernel_mappings(pgd_t *pgd)
123{
124 memcpy(pgd + USER_PTRS_PER_PGD,
125 init_mm.pgd + USER_PTRS_PER_PGD,
126 (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
127}
128
129static inline pgd_t *pgd_alloc(struct mm_struct *mm)
130{
131 pgd_t *pgd;
132
133 pgd = __pgd_alloc(mm, 0);
134 if (likely(pgd != NULL)) {
135 /* Copy kernel mappings */
136 sync_kernel_mappings(pgd);
137 }
138 return pgd;
139}
140
141#ifndef __PAGETABLE_PMD_FOLDED
142
143static inline void __pmd_free_tlb(struct mmu_gather *tlb, pmd_t *pmd,
144 unsigned long addr)
145{
146 riscv_tlb_remove_ptdesc(tlb, virt_to_ptdesc(pmd));
147}
148
149#endif /* __PAGETABLE_PMD_FOLDED */
150
151static inline void __pte_free_tlb(struct mmu_gather *tlb, pgtable_t pte,
152 unsigned long addr)
153{
154 riscv_tlb_remove_ptdesc(tlb, page_ptdesc(pte));
155}
156#endif /* CONFIG_MMU */
157
158#endif /* _ASM_RISCV_PGALLOC_H */